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Nanotechnologies involving physical methods of tumor destruction using functional oligonucleotides are promising for targeted cancer therapy. Our study presents magnetodynamic therapy for selective elimination of tumor cells in vivo using DNA aptamer-functionalized magnetic nanoparticles exposed to a low frequency alternating magnetic field. We developed an enhanced targeting approach of cancer cells with aptamers and arabinogalactan. Aptamers to fibronectin (AS-14) and heat shock cognate 71 kDa protein (AS-42) facilitated the delivery of the nanoparticles to Ehrlich carcinoma cells, and arabinogalactan (AG) promoted internalization through asialoglycoprotein receptors. Specific delivery of the aptamer-modified FeAG nanoparticles to the tumor site was confirmed by magnetic resonance imaging (MRI). After the following treatment with a low frequency alternating magnetic field, AS-FeAG caused cancer cell death in vitro and tumor reduction in vivo. Histological analyses showed mechanical disruption of tumor tissues, total necrosis, cell lysis, and disruption of the extracellular matrix. The enhanced targeted magnetic theranostics with the aptamer conjugated superparamagnetic ferroarabinogalactans opens up a new venue for making biocompatible contrasting agents for MRI imaging and performing non-invasive anti-cancer therapies with a deep penetrated magnetic field. [ABSTRACT FROM AUTHOR]

Here, we report on ZnO nanoparticles (NPs) generated by nanosecond pulsed laser (Nd:YAG, 1064 nm) through ablation of metallic Zn target in water and air and their comparative analysis as potential nanomaterials for biomedical applications. The prepared nanomaterials were carefully characterized in terms of their structure, composition, morphology and defects. It was found that in addition to the main wurtzite ZnO phase, which is conventionally prepared and reported by others, the sample laser generated in air also contained some amount of monoclinic zinc hydroxynitrate. Both nanomaterials were then used to modify model wound dressings based on biodegradable poly l-lactic acid. The as-prepared model dressings were tested as biomedical materials with bactericidal properties towards S. aureus and E. coli strains. The advantages of the NPs prepared in air over their counterparts generated in water found in this work are discussed. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Magnetic nanomaterials were formed by pulsed laser ablation of iron in water and air. • Material ablated in water contained spherical particles of Fe 3 O 4 , Fe 2 O 3 , FeO and Fe. • Material ablated in air contained more Fe 3 O 4 and nitrogen (N-O, N-H or FeN x) • The surface composition and electrokinetic properties of the materials differed. • Material obtained in air is more stable in colloids due to its surface composition. Abstract Magnetic nanomaterials were synthesized using a method of pulsed laser ablation of an iron target in water (PLAL) and in air (PLAG). The microstructure and composition of the obtained materials differed. Spherical nanoparticles (NPs) of 2–80 nm containing Fe 3 O 4 , α-Fe 2 O 3 , γ-Fe 2 O 3 , FeO and Fe were obtained using PLAL. According to the XPS and FTIR data, the surfaces of these particles contained both Fe 3 O 4 and Fe 2 O 3. PLAG led to the formation of NPs of 2–120 nm and 2-D lamellar structures up to 1 μm. This material contained more magnetite and nitrogen species, presumably iron nitrides. This material's surface contained FeOOH; the OH-group content was very high. It exhibited the greatest sedimentation stability and zeta potential value, while magnetic NPs (MNPs) obtained in water were less stable in colloids. The difference in the magnetic parameters of the two materials can be connected to not only the different composition (different magnetite content and nitrogen species presence) but also their structural features. Thus, PLAL and PLAG methods allowed for obtaining magnetic nanostructured materials with different characteristics suitable for application in different fields. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Pulsed laser ablation of iron in air led to magnetite and iron nitrides formation. • Lamellas and rolls appear in the sample that was ablated in air, not in Ar-O 2 mixture. • Thermal treatment allowed control of the composition and structure of the material. • Materials obtained with different properties are in demand for different applications. Abstract Magnetic nanoparticles were obtained using the nanosecond pulsed laser ablation (Nd:YAG laser, 1064 nm, 7 ns) of an iron target in air at atmospheric pressure. The particles obtained were further annealed at four different temperatures. The composition, structure and properties of all obtained powders were investigated using X-ray diffraction (XRD), DSC, attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR), Raman spectroscopy, TEM, SAED and other techniques. The initial sample was found to contain monoclinic magnetite and iron nitrides. Presumably, magnetite presents in the form of spherical particles with the distribution maximum of 12–15 nm, and nitrides take the form of lamellas and rolls. Thermal treatment of the sample led to particle enlargement and phase transformations, first, to cubic magnetite, then to a Fe 3 O 4 , α-Fe 2 O 3 and γ-Fe 2 O 3 mixture, and finally to the pure hematite phase. Zeta-potential, BET surface area and magnetic properties changed with the annealing as well. The obtained materials exhibited different properties that make them in demand in different fields, from biomedicine to technology. [ABSTRACT FROM AUTHOR]